CLIFFS NATURAL RESOURCES INC.

Q: Jun 30 2026

Q: Mar 31 2026

FY: Dec 31 2025

Q: Sep 30 2025

Q: Jun 30 2025

Q: Mar 31 2025

FY: Dec 31 2024

Q: Sep 30 2024

Q: Jun 30 2024

Q: Mar 31 2024

FY: Dec 31 2023

Q: Sep 30 2023

Q: Jun 30 2023

Q: Mar 31 2023

FY: Dec 31 2022

Q: Sep 30 2022

Q: Jun 30 2022

Q: Mar 31 2022

FY: Dec 31 2021

Q: Sep 30 2021

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

Results of Operations and Financial Condition

Submission of Matters to a Vote of Security Holders

Results of Operations and Financial Condition

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

Results of Operations and Financial Condition

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

Other Events

Results of Operations and Financial Condition

Entry into a Material Definitive Agreement

Other Events

Entry into a Material Definitive Agreement

Other Events

Results of Operations and Financial Condition

Submission of Matters to a Vote of Security Holders

Results of Operations and Financial Condition

Results of Operations and Financial Condition

Entry into a Material Definitive Agreement

Results of Operations and Financial Condition

Financial Statements and Exhibits

Prospectus Supplement for Primary Offering

Automatic Shelf Registration

Prospectus Supplement for Primary Offering

Written communication about a business combination transaction (Rule 425)

Written communication about a business combination transaction (Rule 425)

Written communication about a business combination transaction (Rule 425)

Written communication about a business combination transaction (Rule 425)

Written communication about a business combination transaction (Rule 425)

Written communication about a business combination transaction (Rule 425)

Written communication about a business combination transaction (Rule 425)

Automatic Shelf Registration

Registration statement under Securities Act of 1933 to be offered to employees pursuant to certain plans

Registration statement under Securities Act of 1933 to be offered to employees pursuant to certain plans

Prospectus Supplement for Primary Offering

Notice of Effectiveness

Registration statement under Securities Act of 1933

Post Effective Amendment to S-8

Post Effective Amendment to S-8

Prospectus Supplement for Primary Offering

Notice of Effectiveness

Additional Information for Proxy Statement/ Votes

Definitive Proxy Statement

Definitive Proxy Statement

Additional Information for Proxy Statement/ Votes

Definitive Proxy Statement

Additional Information for Proxy Statement/ Votes

Additional Information for Proxy Statement/ Votes

Definitive Proxy Statement

Definitive Proxy Statement

Additional Information for Proxy Statement/ Votes

Additional Information for Proxy Statement/ Votes

Definitive Proxy Statement

Preliminary Proxy Statement

Additional Information for Proxy Statement/ Votes

Definitive Proxy Statement

Additional Information for Proxy Statement/ Votes

Additional Information for Proxy Statement/ Votes

Definitive Proxy Statement

Additional Information for Proxy Statement/ Votes

Additional Information for Proxy Statement/ Votes

Bloom Ron A.

CRONIN JANE M.

STATE STREET CORP

CRONIN JANE M.

Bloom Ron A.

Goncalves Celso L Jr

Goncalves Celso L Jr

Taylor Douglas C

STATE STREET CORP

VANGUARD CAPITAL MANAGEMENT LLC

MICHAEL RALPH S III

Oren Ben

Yocum Arlene M

BALDWIN JOHN T

Bloom Ron A.

Camara Edilson

CRONIN JANE M.

Taylor Douglas C

CRONIN JANE M.

Bloom Ron A.

Specialized Disclosure Report

Specialized Disclosure Report

Annual Report Scanned (Paper)

Specialized Disclosure Report

Specialized Disclosure Report

Annual Report Scanned (Paper)

Specialized Disclosure Report

Specialized Disclosure Report

Annual Report Scanned (Paper)

Specialized Disclosure Report

Annual Report Scanned (Paper)

Specialized Disclosure Report

Specialized Disclosure Report

Correspondence with the SEC

Letter from the SEC

Correspondence with the SEC

No description available

No description available

Annual reports of employee stock purchase savings and similar plans pursuant to Section 15(d)

Specialized Disclosure Report